39x13.50R20 tire size
39x13.50R20 is a flotation (inch) size: 39.0" tall, 13.5" wide, on a 20" rim — about a 340/70R20. The sidewall is 9.5" and the tire turns 517 times per mile.
39x13.50R20 specs
| Overall diameter (height) | 39.00" · 991 mm |
|---|---|
| Section width | 13.50" · 343 mm |
| Sidewall height | 9.50" · 241 mm (70% of width) |
| Rim diameter | 20" |
| Circumference | 122.52" · 3.112 m |
| Revolutions per mile | 517 (321 per km) |
| Closest metric size | 340/70R20 |
Equivalent sizes on a 20" rim
Sizes within ±5% of the overall diameter. Green rows are inside the usual ±3% limit for keeping the speedometer, ABS and gearing right; red rows are bigger changes that need clearance checks.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 38x13.50R20 | 38.00" | -2.56% | 0 mm | 58.5 mph | calculate → |
| 38x15.50R20 | 38.00" | -2.56% | +51 mm | 58.5 mph | calculate → |
| 40x15.50R20 | 40.00" | +2.56% | +51 mm | 61.5 mph | calculate → |
| 40x14.50R20 | 40.00" | +2.56% | +25 mm | 61.5 mph | calculate → |
| 39.5x13.50R20 | 39.50" | +1.28% | 0 mm | 60.8 mph | calculate → |
| 38x14.50R20 | 38.00" | -2.56% | +25 mm | 58.5 mph | calculate → |
| 40x13.50R20 | 40.00" | +2.56% | 0 mm | 61.5 mph | calculate → |
| 395/60R20 | 38.66" | -0.87% | +52 mm | 59.5 mph | calculate → |
| 38.5x13.50R20 | 38.50" | -1.28% | 0 mm | 59.2 mph | calculate → |
| 38.5x14.50R20 | 38.50" | -1.28% | +25 mm | 59.2 mph | calculate → |
| 38x11.50R20 | 38.00" | -2.56% | -51 mm | 58.5 mph | calculate → |
| 39.5x15.00R20 | 39.50" | +1.28% | +38 mm | 60.8 mph | calculate → |
Try another size against 39x13.50R20
Questions
What size is 39x13.50R20 in inches?
39x13.50R20 is about 39.0" tall and 13.5" wide on a 20-inch rim — roughly a 340/70R20 in inch sizing.
What does 39x13.50R20 mean?
39" overall diameter, 13.50" section width, radial, 20" rim.
What tire sizes are equivalent to 39x13.50R20?
On the same 20" rim, within 3% of the diameter: 395/60R20 (-0.87%), 38.5x13.50R20 (-1.28%), 38.5x14.50R20 (-1.28%), 39.5x13.50R20 (+1.28%), 39.5x15.00R20 (+1.28%), 38x11.50R20 (-2.56%).
How many revolutions per mile does a 39x13.50R20 tire make?
About 517 revolutions per mile (circumference 122.5").
How these numbers are computed
Diameter = rim + 2 × sidewall, sidewall = width × aspect ÷ 100, circumference = π × diameter, revolutions per mile = 63,360 ÷ circumference. Real tires differ by brand by a few tenths of an inch. Last reviewed October 14, 2026.